Starting triangular output signal

Greetings,
I made this VI, but there's an error in it and I don't think it's solvable like this.
The triangular output signal should start when I press the boolean. Else the DAQ Assistant should put out 0V.
Also when I press the stop button the DAQ Assistant has to put out 0V
Is there another solution?
Thanks
Solved!
Go to Solution.
Attachments:
Screenshot.png ‏23 KB

I recently made a solution by using the "Select" function.
The Triangle Pattern produces the pattern I want the DAQ Assistant to send out the Output Signal.
I'm using a USB 6008.
But now I have a different issue. When I press the Start button, there's a sudden high pulse of 1V and then the output continues the regular Triangle Pattern.
Attachments:
Triangle voltage .jpg ‏35 KB

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Message Edited by _Pavel_ on 10-28-2009 05:21 PM
Solved!
Go to Solution.

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I want to create a simple sine wave output on a PXI-5421 card. I have looked at the sample projects for DAQmx, and based an application on them.
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***** START OF OUTPUT *****
DAQmxResetDevice -> SUCCESS
DAQmxCreateTask -> SUCCESS
DAQmxCreateAOVoltageChan -> SUCCESS
DAQmxCfgSampClkTiming -> SUCCESS
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Property: DAQmx_SampClk_Src
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***** END OF OUTPUT *****
***** START OF APPLICATION *****
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***** END OF APPLICATION *****

Broccoli wrote:
I want to create a simple sine wave output on a PXI-5421 card. I have looked at the sample projects for DAQmx, and based an application on them.
The application falls over at the call to DAQmxWriteAnalogF64 using the following parameters:
lReturn = DAQmxWriteAnalogF64(
m_hTask,
1000,
0,
10.0,
DAQmx_Val_GroupByChannel,
data,
&lWritten,
NULL
What am I doing wrong?
Below is the output of the application, and the code.
***** START OF OUTPUT *****
DAQmxResetDevice -> SUCCESS
DAQmxCreateTask -> SUCCESS
DAQmxCreateAOVoltageChan -> SUCCESS
DAQmxCfgSampClkTiming -> SUCCESS
Samples per channel written: 0
Source terminal to be routed could not be found on the device.
Make sure the terminal name is valid for the specified device. Refer to Measurement & Automation Explorer for valid terminal names.
Device: PXI1Slot3
Property: DAQmx_SampClk_Src
Source Terminal:
Task Name: _unnamedTask<0>
Status Code: -200040
DAQmxWriteAnalogF64 -> -200040
***** END OF OUTPUT *****
***** START OF APPLICATION *****
void Startup( void )
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double dblAmplitude = 5; // 5 volts
// generate wave data
float64 data[1000];
for( int i=0; i<1000; i++ )
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m_hTask,
1000,
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10.0,
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data,
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NULL
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***** END OF APPLICATION *****
Hello Broccoli,
NI-DAQmx is not a supported API for the NI-5421 AWG. For all NI Signal Generators, please use the NI-FGEN API, which shipped with your instrument. You may also download NI-FGEN (2.2.1 as of today) from
http://digital.ni.com/softlib.nsf/954feaeea92d90918625674b00658b83/8b1f32b4b8f7148586256efd006075a9?OpenDocument
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Marcos Kirsch
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Marcos Kirsch
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